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in the absence of other forces than gravity, any object thrown from the ground will return with exactly the same speed
to see this, note that the height h of the missile is
h = 0 + 9.8t - 4.9t^2
= 4.9t(2-t)
the velocity is
v = 9.8-9.8t
= 9.8(1-t)
so, at t=2, v = 9.9(1-2) = -9.8
same speed, opposite direction